Field of the Invention
The present invention relates to a male member and a tool changer.
Description of the Related Art
As a tool changer applied to various equipment such as industrial robots, a tool changer equipped with a male member mounted on a robot side and a female member attached to a tool side is known (e.g., Japanese Patent Laid-Open No. 2012-250327). The male member includes a male member body on which a protrusion is formed and a cylinder unit built into the male member body. The protrusion contains plural cams operated in the cylinder unit. Each cam pivots between an engagement position at which the cam is engaged with an engaging member on the female member by projecting from the protrusion and a disengagement position at which the cam is disengaged from the engaging member and retracted into the protrusion. A coupling hole is formed in the female member to accept insertion of the protrusion and the engaging member is provided in the back of an opening made in an inner circumferential surface of the coupling hole. In the tool changer, with the protrusion inserted in the coupling hole, each cam engages with the engaging member, thereby coupling together the male member and female member. Also, by disengaging the cams and the engaging member from each other, the male member and female member can be separated from each other.
In this way, the tool changer can change the tool mounted on an industrial robot.
In the tool changer, to prevent the industrial robot from operating under imperfectly coupled conditions two proximity sensors are installed for each cam to detect whether the cam is at the engagement position or disengagement position. In this case, one of the proximity sensors is installed facing on the cam at the engagement position and the other proximity sensor is installed facing on the cam at the disengagement position. Also, a configuration is known in which one of the proximity sensors is installed facing on the cam at the engagement position and the other proximity sensor is installed at a position facing on a piston in a cylinder unit when the cam reaches the disengagement position (see Japanese Patent Laid-Open No. 5-301186).
With the configuration in which two proximity sensors are installed for each cam as described above, it is difficult to downsize the male member. Also, when the proximity sensor is installed facing on a cam, the cam is exposed outside, making it necessary to expose at least part of the proximity sensor, such as a detection surface, to the outside and thereby raising fears that the proximity sensor might be damaged.
An object of the present invention is to provide a male member and tool changer which are advantageous for downsizing and capable of preventing damage to proximity sensors.